North Korea's nuclear tantrum

February 13, 2013

South Korean activists protest North Korean leader Kim Jong Un and his country’s nuclear ambitions during a recent rally in Seoul, the South’s capital. Tuesday’s nuclear test made clear that Kim is not intent on taking his nation down a less confrontational path. (KIM JAE-HWAN, AFP/Getty Images)

Over the next days, we'll learn more vital details about Tuesday's nuclear test by North Korea.

We'll discover how powerful the blast was — Pyongyang's first test in 2006 was widely seen as a partial dud. Its second in 2009 was more impressive but still smaller than expected. Early estimates of Tuesday's blast suggest the North Koreans are beginning to master nuclear devices with substantial explosive power.

We'll likely learn if Pyongyang has built a nuclear weapon of enriched uranium, a major step in its ability to amass a much larger nuclear arsenal.

Most ominously, we may get hints about whether the North has made significant progress in developing a warhead small enough to fit atop a long-range missile and threaten the United States or its allies. A recent rocket launch was deemed a success by arms experts, meaning North Korea could eventually lob a nuclear-tipped missile as far as the United States mainland.

This latest nuclear test is significant, too, for another reason: It buries any hopes that new leader Kim Jong Un would ratchet down the bluster and threats and try harder to feed his starving people.

North Korea's nuclear tantrum is a familiar warning to the U.S. and its allies: Don't mess with us. And don't ignore us.

On Tuesday, North Korea could not be ignored. The U.N. Security Council scrambled into emergency session and may vote fresh sanctions against North Korea. But the North has been sanctioned over and over by the Security Council. The North Korean economy is crippled and its fledgling leader doesn't mind piling more hardships on his citizens. Or perhaps he's more afraid of angering the country's military mandarins, whom he needs to stay in power.

One thing is certain: In Kim's calculation, more nuclear and missile tests carry a lower cost to North Korea than standing down. The only way to change that calculus is to ratchet up the cost for Pyongyang's defiance.

U.S. pressure — or inducements of food and other aid — won't force the regime to back down. Been there, tried that. Again and again.

North Korea's main ally, China, still holds the greatest leverage: The Chinese can slow food and oil deliveries, crimping Pyongyang's trade even more.

The Chinese aren't eager to topple the regime, sending thousands of refugees over its borders. There are hints, however, that Xi Jinping, the new head of the Communist Party and incoming Chinese president, may be willing to turn up the pressure on the North Koreans. China surprised Western officials by signing on to U.N. Security Council sanctions last month that froze North Korean assets and banned travel by North Korean officials.

Xi has said he wants "a new type of relationship" between the U.S. and China. Here's a start: Persuade the North Koreans to back off.

Otherwise, there's one inescapable conclusion from this nuclear test. There will be more. The North Korean threat is growing. There's nothing on the horizon to stop it.